EL4121 Embedded System / mbed-os

Dependents:   cobaLCDJoyMotor_Thread odometry_omni_3roda_v3 odometry_omni_3roda_v1 odometry_omni_3roda_v2 ... more

features/mbedtls/src/arc4.c@0:b74591d5ab33, 2017-12-11 (annotated)

Committer:
be_bryan
Date:
Mon Dec 11 17:54:04 2017 +0000
Revision:
0:b74591d5ab33
motor ++

Who changed what in which revision?

UserRevisionLine numberNew contents of line
be_bryan 0:b74591d5ab33 1 /*
be_bryan 0:b74591d5ab33 2 * An implementation of the ARCFOUR algorithm
be_bryan 0:b74591d5ab33 3 *
be_bryan 0:b74591d5ab33 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
be_bryan 0:b74591d5ab33 5 * SPDX-License-Identifier: Apache-2.0
be_bryan 0:b74591d5ab33 6 *
be_bryan 0:b74591d5ab33 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
be_bryan 0:b74591d5ab33 8 * not use this file except in compliance with the License.
be_bryan 0:b74591d5ab33 9 * You may obtain a copy of the License at
be_bryan 0:b74591d5ab33 10 *
be_bryan 0:b74591d5ab33 11 * http://www.apache.org/licenses/LICENSE-2.0
be_bryan 0:b74591d5ab33 12 *
be_bryan 0:b74591d5ab33 13 * Unless required by applicable law or agreed to in writing, software
be_bryan 0:b74591d5ab33 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
be_bryan 0:b74591d5ab33 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
be_bryan 0:b74591d5ab33 16 * See the License for the specific language governing permissions and
be_bryan 0:b74591d5ab33 17 * limitations under the License.
be_bryan 0:b74591d5ab33 18 *
be_bryan 0:b74591d5ab33 19 * This file is part of mbed TLS (https://tls.mbed.org)
be_bryan 0:b74591d5ab33 20 */
be_bryan 0:b74591d5ab33 21 /*
be_bryan 0:b74591d5ab33 22 * The ARCFOUR algorithm was publicly disclosed on 94/09.
be_bryan 0:b74591d5ab33 23 *
be_bryan 0:b74591d5ab33 24 * http://groups.google.com/group/sci.crypt/msg/10a300c9d21afca0
be_bryan 0:b74591d5ab33 25 */
be_bryan 0:b74591d5ab33 26
be_bryan 0:b74591d5ab33 27 #if !defined(MBEDTLS_CONFIG_FILE)
be_bryan 0:b74591d5ab33 28 #include "mbedtls/config.h"
be_bryan 0:b74591d5ab33 29 #else
be_bryan 0:b74591d5ab33 30 #include MBEDTLS_CONFIG_FILE
be_bryan 0:b74591d5ab33 31 #endif
be_bryan 0:b74591d5ab33 32
be_bryan 0:b74591d5ab33 33 #if defined(MBEDTLS_ARC4_C)
be_bryan 0:b74591d5ab33 34
be_bryan 0:b74591d5ab33 35 #include "mbedtls/arc4.h"
be_bryan 0:b74591d5ab33 36
be_bryan 0:b74591d5ab33 37 #include <string.h>
be_bryan 0:b74591d5ab33 38
be_bryan 0:b74591d5ab33 39 #if defined(MBEDTLS_SELF_TEST)
be_bryan 0:b74591d5ab33 40 #if defined(MBEDTLS_PLATFORM_C)
be_bryan 0:b74591d5ab33 41 #include "mbedtls/platform.h"
be_bryan 0:b74591d5ab33 42 #else
be_bryan 0:b74591d5ab33 43 #include <stdio.h>
be_bryan 0:b74591d5ab33 44 #define mbedtls_printf printf
be_bryan 0:b74591d5ab33 45 #endif /* MBEDTLS_PLATFORM_C */
be_bryan 0:b74591d5ab33 46 #endif /* MBEDTLS_SELF_TEST */
be_bryan 0:b74591d5ab33 47
be_bryan 0:b74591d5ab33 48 #if !defined(MBEDTLS_ARC4_ALT)
be_bryan 0:b74591d5ab33 49
be_bryan 0:b74591d5ab33 50 /* Implementation that should never be optimized out by the compiler */
be_bryan 0:b74591d5ab33 51 static void mbedtls_zeroize( void *v, size_t n ) {
be_bryan 0:b74591d5ab33 52 volatile unsigned char *p = (unsigned char*)v; while( n-- ) *p++ = 0;
be_bryan 0:b74591d5ab33 53 }
be_bryan 0:b74591d5ab33 54
be_bryan 0:b74591d5ab33 55 void mbedtls_arc4_init( mbedtls_arc4_context *ctx )
be_bryan 0:b74591d5ab33 56 {
be_bryan 0:b74591d5ab33 57 memset( ctx, 0, sizeof( mbedtls_arc4_context ) );
be_bryan 0:b74591d5ab33 58 }
be_bryan 0:b74591d5ab33 59
be_bryan 0:b74591d5ab33 60 void mbedtls_arc4_free( mbedtls_arc4_context *ctx )
be_bryan 0:b74591d5ab33 61 {
be_bryan 0:b74591d5ab33 62 if( ctx == NULL )
be_bryan 0:b74591d5ab33 63 return;
be_bryan 0:b74591d5ab33 64
be_bryan 0:b74591d5ab33 65 mbedtls_zeroize( ctx, sizeof( mbedtls_arc4_context ) );
be_bryan 0:b74591d5ab33 66 }
be_bryan 0:b74591d5ab33 67
be_bryan 0:b74591d5ab33 68 /*
be_bryan 0:b74591d5ab33 69 * ARC4 key schedule
be_bryan 0:b74591d5ab33 70 */
be_bryan 0:b74591d5ab33 71 void mbedtls_arc4_setup( mbedtls_arc4_context *ctx, const unsigned char *key,
be_bryan 0:b74591d5ab33 72 unsigned int keylen )
be_bryan 0:b74591d5ab33 73 {
be_bryan 0:b74591d5ab33 74 int i, j, a;
be_bryan 0:b74591d5ab33 75 unsigned int k;
be_bryan 0:b74591d5ab33 76 unsigned char *m;
be_bryan 0:b74591d5ab33 77
be_bryan 0:b74591d5ab33 78 ctx->x = 0;
be_bryan 0:b74591d5ab33 79 ctx->y = 0;
be_bryan 0:b74591d5ab33 80 m = ctx->m;
be_bryan 0:b74591d5ab33 81
be_bryan 0:b74591d5ab33 82 for( i = 0; i < 256; i++ )
be_bryan 0:b74591d5ab33 83 m[i] = (unsigned char) i;
be_bryan 0:b74591d5ab33 84
be_bryan 0:b74591d5ab33 85 j = k = 0;
be_bryan 0:b74591d5ab33 86
be_bryan 0:b74591d5ab33 87 for( i = 0; i < 256; i++, k++ )
be_bryan 0:b74591d5ab33 88 {
be_bryan 0:b74591d5ab33 89 if( k >= keylen ) k = 0;
be_bryan 0:b74591d5ab33 90
be_bryan 0:b74591d5ab33 91 a = m[i];
be_bryan 0:b74591d5ab33 92 j = ( j + a + key[k] ) & 0xFF;
be_bryan 0:b74591d5ab33 93 m[i] = m[j];
be_bryan 0:b74591d5ab33 94 m[j] = (unsigned char) a;
be_bryan 0:b74591d5ab33 95 }
be_bryan 0:b74591d5ab33 96 }
be_bryan 0:b74591d5ab33 97
be_bryan 0:b74591d5ab33 98 /*
be_bryan 0:b74591d5ab33 99 * ARC4 cipher function
be_bryan 0:b74591d5ab33 100 */
be_bryan 0:b74591d5ab33 101 int mbedtls_arc4_crypt( mbedtls_arc4_context *ctx, size_t length, const unsigned char *input,
be_bryan 0:b74591d5ab33 102 unsigned char *output )
be_bryan 0:b74591d5ab33 103 {
be_bryan 0:b74591d5ab33 104 int x, y, a, b;
be_bryan 0:b74591d5ab33 105 size_t i;
be_bryan 0:b74591d5ab33 106 unsigned char *m;
be_bryan 0:b74591d5ab33 107
be_bryan 0:b74591d5ab33 108 x = ctx->x;
be_bryan 0:b74591d5ab33 109 y = ctx->y;
be_bryan 0:b74591d5ab33 110 m = ctx->m;
be_bryan 0:b74591d5ab33 111
be_bryan 0:b74591d5ab33 112 for( i = 0; i < length; i++ )
be_bryan 0:b74591d5ab33 113 {
be_bryan 0:b74591d5ab33 114 x = ( x + 1 ) & 0xFF; a = m[x];
be_bryan 0:b74591d5ab33 115 y = ( y + a ) & 0xFF; b = m[y];
be_bryan 0:b74591d5ab33 116
be_bryan 0:b74591d5ab33 117 m[x] = (unsigned char) b;
be_bryan 0:b74591d5ab33 118 m[y] = (unsigned char) a;
be_bryan 0:b74591d5ab33 119
be_bryan 0:b74591d5ab33 120 output[i] = (unsigned char)
be_bryan 0:b74591d5ab33 121 ( input[i] ^ m[(unsigned char)( a + b )] );
be_bryan 0:b74591d5ab33 122 }
be_bryan 0:b74591d5ab33 123
be_bryan 0:b74591d5ab33 124 ctx->x = x;
be_bryan 0:b74591d5ab33 125 ctx->y = y;
be_bryan 0:b74591d5ab33 126
be_bryan 0:b74591d5ab33 127 return( 0 );
be_bryan 0:b74591d5ab33 128 }
be_bryan 0:b74591d5ab33 129
be_bryan 0:b74591d5ab33 130 #endif /* !MBEDTLS_ARC4_ALT */
be_bryan 0:b74591d5ab33 131
be_bryan 0:b74591d5ab33 132 #if defined(MBEDTLS_SELF_TEST)
be_bryan 0:b74591d5ab33 133 /*
be_bryan 0:b74591d5ab33 134 * ARC4 tests vectors as posted by Eric Rescorla in sep. 1994:
be_bryan 0:b74591d5ab33 135 *
be_bryan 0:b74591d5ab33 136 * http://groups.google.com/group/comp.security.misc/msg/10a300c9d21afca0
be_bryan 0:b74591d5ab33 137 */
be_bryan 0:b74591d5ab33 138 static const unsigned char arc4_test_key[3][8] =
be_bryan 0:b74591d5ab33 139 {
be_bryan 0:b74591d5ab33 140 { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF },
be_bryan 0:b74591d5ab33 141 { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF },
be_bryan 0:b74591d5ab33 142 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
be_bryan 0:b74591d5ab33 143 };
be_bryan 0:b74591d5ab33 144
be_bryan 0:b74591d5ab33 145 static const unsigned char arc4_test_pt[3][8] =
be_bryan 0:b74591d5ab33 146 {
be_bryan 0:b74591d5ab33 147 { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF },
be_bryan 0:b74591d5ab33 148 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
be_bryan 0:b74591d5ab33 149 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
be_bryan 0:b74591d5ab33 150 };
be_bryan 0:b74591d5ab33 151
be_bryan 0:b74591d5ab33 152 static const unsigned char arc4_test_ct[3][8] =
be_bryan 0:b74591d5ab33 153 {
be_bryan 0:b74591d5ab33 154 { 0x75, 0xB7, 0x87, 0x80, 0x99, 0xE0, 0xC5, 0x96 },
be_bryan 0:b74591d5ab33 155 { 0x74, 0x94, 0xC2, 0xE7, 0x10, 0x4B, 0x08, 0x79 },
be_bryan 0:b74591d5ab33 156 { 0xDE, 0x18, 0x89, 0x41, 0xA3, 0x37, 0x5D, 0x3A }
be_bryan 0:b74591d5ab33 157 };
be_bryan 0:b74591d5ab33 158
be_bryan 0:b74591d5ab33 159 /*
be_bryan 0:b74591d5ab33 160 * Checkup routine
be_bryan 0:b74591d5ab33 161 */
be_bryan 0:b74591d5ab33 162 int mbedtls_arc4_self_test( int verbose )
be_bryan 0:b74591d5ab33 163 {
be_bryan 0:b74591d5ab33 164 int i, ret = 0;
be_bryan 0:b74591d5ab33 165 unsigned char ibuf[8];
be_bryan 0:b74591d5ab33 166 unsigned char obuf[8];
be_bryan 0:b74591d5ab33 167 mbedtls_arc4_context ctx;
be_bryan 0:b74591d5ab33 168
be_bryan 0:b74591d5ab33 169 mbedtls_arc4_init( &ctx );
be_bryan 0:b74591d5ab33 170
be_bryan 0:b74591d5ab33 171 for( i = 0; i < 3; i++ )
be_bryan 0:b74591d5ab33 172 {
be_bryan 0:b74591d5ab33 173 if( verbose != 0 )
be_bryan 0:b74591d5ab33 174 mbedtls_printf( " ARC4 test #%d: ", i + 1 );
be_bryan 0:b74591d5ab33 175
be_bryan 0:b74591d5ab33 176 memcpy( ibuf, arc4_test_pt[i], 8 );
be_bryan 0:b74591d5ab33 177
be_bryan 0:b74591d5ab33 178 mbedtls_arc4_setup( &ctx, arc4_test_key[i], 8 );
be_bryan 0:b74591d5ab33 179 mbedtls_arc4_crypt( &ctx, 8, ibuf, obuf );
be_bryan 0:b74591d5ab33 180
be_bryan 0:b74591d5ab33 181 if( memcmp( obuf, arc4_test_ct[i], 8 ) != 0 )
be_bryan 0:b74591d5ab33 182 {
be_bryan 0:b74591d5ab33 183 if( verbose != 0 )
be_bryan 0:b74591d5ab33 184 mbedtls_printf( "failed\n" );
be_bryan 0:b74591d5ab33 185
be_bryan 0:b74591d5ab33 186 ret = 1;
be_bryan 0:b74591d5ab33 187 goto exit;
be_bryan 0:b74591d5ab33 188 }
be_bryan 0:b74591d5ab33 189
be_bryan 0:b74591d5ab33 190 if( verbose != 0 )
be_bryan 0:b74591d5ab33 191 mbedtls_printf( "passed\n" );
be_bryan 0:b74591d5ab33 192 }
be_bryan 0:b74591d5ab33 193
be_bryan 0:b74591d5ab33 194 if( verbose != 0 )
be_bryan 0:b74591d5ab33 195 mbedtls_printf( "\n" );
be_bryan 0:b74591d5ab33 196
be_bryan 0:b74591d5ab33 197 exit:
be_bryan 0:b74591d5ab33 198 mbedtls_arc4_free( &ctx );
be_bryan 0:b74591d5ab33 199
be_bryan 0:b74591d5ab33 200 return( ret );
be_bryan 0:b74591d5ab33 201 }
be_bryan 0:b74591d5ab33 202
be_bryan 0:b74591d5ab33 203 #endif /* MBEDTLS_SELF_TEST */
be_bryan 0:b74591d5ab33 204
be_bryan 0:b74591d5ab33 205 #endif /* MBEDTLS_ARC4_C */